var imgMaxWidth  = 630; //图片最大宽度
var imgMaxHeight = 450; //图片最大高度

var _playSpeed = 5;//自动播放速度 秒
var _playSwitch = true;//自动播放开关
var _subjectIndex=0;
var _picIndex=0; 
var _playTimer;

var _xmlDocName = "pics.xml";
var _picSubAry  = new Array();
var _picUrlAry  = new Array();
var _picTxtAry  = new Array();

var obj_SubDiv = document.getElementById("subjectDiv");
var obj_Img = document.getElementById("picShow");
var obj_TxtDiv = document.getElementById("txtShowDiv");
var obj_PageDiv = document.getElementById("pageLinkDiv");

function init(subInx,picInx){
	_playSwitch = true;
	_playSpeed = _playSpeed*1000;
	parseXML();
	if(Number(subInx)>=_picSubAry.length || Number(subInx)<0)subInx=0;
	if(Number(picInx)>=_picUrlAry[subInx].length || Number(picInx)<0)picInx=0;
	_subjectIndex=subInx;
	_picIndex=picInx;
}

function PicShow(){
	if(_picIndex >= _picUrlAry[_subjectIndex].length-1){
		obj_Img.title="Last page";
	}else{
		obj_Img.title="Next page";
		obj_Img.style.cursor ="pointer";
		obj_Img.onclick=PicShowNext;
	}
	obj_Img.src=_picUrlAry[_subjectIndex][_picIndex];
	obj_TxtDiv.innerHTML=_picTxtAry[_subjectIndex][_picIndex];
	obj_PageDiv.innerHTML=GetPageLink(_subjectIndex,_picIndex);
	obj_SubDiv.innerHTML =GetSubLink(_subjectIndex);
}
function PicShowNext(){
	_picIndex++;
	if(_picIndex >= _picUrlAry[_subjectIndex].length){
		return;
	}
	//PicShow();
	window.location.href="?sub="+_subjectIndex.toString()+"&p="+_picIndex.toString();
}
function PicPlaySwitch(){
	if(_playSwitch){
		_playSwitch=false;
	}else{
		_playSwitch=true;
		PicPlay();
	}
}
function PicPlay(){
	_playSwitch=true;
	PlayTimervalHandler();
}
function ClearPicPlay(){
	if(_playTimer)clearInterval(_playTimer);
}
function PlayTimervalHandler(){
	if(_picIndex >= _picUrlAry[_subjectIndex].length){
		//_picIndex=0;
		_playSwitch=true;
		PicPlaySwitch();
		return;
	}
	
	PicShow();
	_picIndex++;
	if(_playSwitch)_playTimer=setTimeout("PlayTimervalHandler()",_playSpeed);
}
function parseXML()
{
  var xmlDoc=null;
  try{ //Internet Explorer
    xmlDoc=new ActiveXObject("Microsoft.XMLDOM");
  }catch(e){
    try{ //Firefox, Mozilla, Opera, etc.
      xmlDoc=document.implementation.createDocument("","",null);
    }catch(e){
      alert('Your browser cannot handle this script.');//alert(e.message);
      return;
    }
  }
  xmlDoc.async=false;
  xmlDoc.load(_xmlDocName);
  var x=xmlDoc.getElementsByTagName("subject");
  for (var i=0;i<x.length;i++){
	  _picSubAry[i]=x[i].getAttribute("text");
	  var tmpUrlAry=new Array();
	  var tmpTxtAry=new Array();
	  var p=x[i].getElementsByTagName("pic");
	  for (var n=0;n<p.length;n++){
		  tmpUrlAry[n]=p[n].getElementsByTagName("url")[0].childNodes[0].nodeValue;
		  tmpTxtAry[n]=p[n].getElementsByTagName("text")[0].childNodes[0].nodeValue=="null"?"":p[n].getElementsByTagName("text")[0].childNodes[0].nodeValue;
		  //tmpTxtAry[n]=typeof(p[n].getElementsByTagName("text"))==undefined?"":p[n].getElementsByTagName("text")[0].childNodes[0].nodeValue;
	  }
	  _picUrlAry[i]=tmpUrlAry;
	  _picTxtAry[i]=tmpTxtAry;
  }
}
function GetSubLink(subInx){
  var reStr="<ul style=\"padding-left:30px\">";
  for (var i=0;i<_picSubAry.length;i++){
	  var classStr = "photo";
	  if(i == subInx){
		  classStr = "photocurr";
	  }
	  reStr += "<li><a href=\"?sub="+i.toString()+"\" class=\""+classStr+"\">"+_picSubAry[i]+"</a></li>";
  }
  reStr+="</ul>";
  return reStr;
}
function GetPageLink(subInx,pageInx){
  var reStr="<ul>";
  for (var i=0;i<_picUrlAry[subInx].length;i++){
	  var classStr = "photo";
	  if(i == pageInx){
		  classStr = "photocurr";
	  }
	  reStr += "<li><a href=\"?sub="+subInx.toString()+"&p="+i.toString()+"\" class=\""+classStr+"\">"+(i+1).toString()+"</a></li>";
  }
  reStr+="</ul>";
  return reStr;
}